A porous honeycomb structure is widely used as a filter for collecting and removing particulates included in dust-containing gas such as exhaust gas from a diesel engine, or as a catalyst carrier for supporting a catalytic component for cleaning up hazardous materials in exhaust gas.
As shown in FIG. 1, in a honeycomb structure 1 of this type, a honeycomb stacked body 3 is formed by bundling a plurality of porous honeycomb segments 2 made of silicon carbide and the like, and a coating material layer 4 is formed around this honeycomb stacked body 3 to construct the entirety. An adhesive layer 9 exists between one honeycomb segment 2 and another honeycomb segment 2.
As shown in FIGS. 2A and 2B, the honeycomb segment 2 includes numerous circulation holes 5 arranged in a longitudinal direction, and partition walls 6 partitioning the circulation holes 5 are configured to function as a filter. As shown in FIG. 2B, either an entrance side (on the left in FIG. 2B) for exhaust gas G or an exit side (on the right in FIG. 2B) is sealed with a filling material 7, whereby the exhaust gas G flowing into one circulation hole 5 passes through the partition wall 6 of the circulation hole 5 and flows out of another circulation hole 5 adjacent thereto.
Incidentally, this honeycomb structure 1 is conventionally manufactured by the method described below (Japanese Unexamined Patent Publication No. 2002-126427).
Firstly, a mixed composition including a solvent, a binder, and the like in addition to ceramic granules as the raw material is prepared, and a ceramic compact is fabricated by performing extrusion molding or the like by use of this mixed composition. Thereafter, the porous honeycomb segment 2 is manufactured by subjecting this ceramic compact to respective processes of drying, degreasing, and firing.
Next, as shown in FIG. 2C, masking materials 8 in which a sticky material layer is formed on a base film are attached to both end surfaces of each honeycomb segment 2.
Thereafter, adhesive paste is coated on side surfaces of the honeycomb segment 2 attaching the masking materials 8, and other honeycomb segments 2 are repeatedly stacked thereon to form the honeycomb stacked body 3.
Next, the entire honeycomb stacked body 3 is heated to dry and harden the adhesive paste. Thereafter, an outer peripheral portion of the honeycomb stacked body 3 is ground into the shape as shown in FIG. 1.
Moreover, the outer peripheral portion of the honeycomb stacked body 3 after grinding is covered with the coating material layer 4, and then the coating material layer 4 is dried. Thereafter, the honeycomb structure 1 is manufactured by separating the masking materials 8.
The separation of the masking materials 8 is performed for instance by pressing a separation sheet (not shown) coated with a sticky material having stronger adhesion than the sticky material in the masking material 8 against the masking material 8, bonding the masking material 8 to the separation sheet, then peeling off the separation sheet, and thereby separating the masking materials 8 from the end surfaces of the honeycomb stacked body 3 (Japanese Unexamined Patent Publication No. 2002-126421).
However, since grinding of the honeycomb stacked body 3 is performed in the state of attaching the masking materials 8, the sticky material in the masking material 8 is bonded to a whetstone used for grinding and causes sudden deterioration of a grinding performance of the whetstone. Accordingly, the whetstone needs to be cleaned or replaced in a short period. As a consequence, there is a problem of causing reduction in operating efficiency.
Accordingly, an object of the present invention is to provide a method of manufacturing a honeycomb structure, which is capable of maximizing a grinding performance of a whetstone for grinding an outer peripheral portion of a honeycomb stacked body into a predetermined shape and thereby enhancing operating efficiency.